Automatic loading apparatus for a charge table

ABSTRACT

A charge table for storing billets until they are required at a grinding location. The billets are successively loaded on the table at a loading station, each billet being pushed forwardly on the table to a pickoff station where they are removed as required. Means are provided whereby billet accumulation takes place in the forward region of the table, thus insuring the presence of a billet at all times at the pickoff station.

0 United States Patent 13,591,021

{72! lnvenlor Frank B.Hall [56] ReierencesCited Chicago UNITED STATES PATENTS 2n Appl No 838.789 7 9 4 L h u Filed y 3l969 3.12 ,029 3/l 6 ugm u l r v i i 214/7 [45] Patented July 6,1971 Primary ExaminerGerald M.Forlenza [73] Assignee Pettibone Mulliken Corporation Assistant Examiner-Lawrence J. Oresky Chicago, Ill. Au0rneyNorman H. Gerlach [54] AUTOMATIC LOADING APPARATUS FOR A CHARGE TABLE I 1 Claims, 8 Drawing Figs.

[52] U.S.Cl 214/7, 214/152 [5 1] Int. Cl 865g 61/00 [50] Field of Search 2l4/7 ABSTRACT: A charge table for storing billets until they are required at a grinding location. The billets are successively loaded on the table at a loading station, each billet being pushed forwardly on the table to a pickoff station where they are removed as required. Means are provided whereby billet accumulation takes place in the forward region of the table, thus insuring the presence of a billet at all times at the pickoff station.

PATENTED JUL 6 |97| SHEET 1 OF 3 L 4 R M 1% w N 6? mH w w N w? N F N s m? m m 1 J 6 F m no 4. LT I: 1 07 0a m \l Iu M :5 m 5 NJ 5. j

0. 0m on. #m mm m PATENTEB JUL BIB?! 3,591,021

/Nl/E/VTOR FRANK HALL By' M Attorney PATENIEU JUL 6 1911 SHEET 3 OF 3 FIG.6

IRM: 1

FIG?

AUTOMATIC LOADING APPARATUS FOR A CHARGE TABLE The present invention relates generally to billet-moving means, and more particularly to an automatic loading apparatus for a steel mill charge table on which billets, slabs, or other workpieces are stored preparatory to transferring them to a grinding or other surfacing operation. More specifically, the invention is concerned with an automatic loading apparatus for that type of charge table wherein billets are loaded onto the table by a transverse conveyor which deposits them at the extreme rear end of the table at a loading station from whence they are pushed forwardly to a pickoff station at the extreme front end of the table. The billets are then withdrawn transversely from the pickoff station as they are required at the grinding location.

Heretofore, it has been the practice in connection with a charge table of the aforementioned type to push the billets, one step at a time, from the loading station to the pickoff station, the billets accumulating as they are received from the rear end of the table, that is, the loading station, the lastreceived billet serving to push the next preceding billet ahead of it until a solid line or series of billets fills the table and extends from the loading station to the pickoff station. Then, at the pickoff station a limit switch prevents further accumulation of billets until the lading billet at the pickoff station has been withdrawn for processing or treatment at the grinding location, thus making room for advance of the entire line or series of billets and creating a vacancy at the loading station for reception of an additional billet. Such a procedure obviously will not accommodate a situation where the grinding location calls for a billet before the table is fully loaded.

Other means including motor-driven dogs which advance the billets in step-bystep fashion with varying limit stop devices for controlling the actuation of the dogs have been devised for advancing the billets from the loading station of the charge table to the pickoff station. These means, however, do not insure the presence of a billet at the pickoff station at all times. For example, they do not guard against a situation where there is one billet at the pickoff station, one billet at the middle of the table, and one billet at the loading station. In such an instance, withdrawal of the billet at the pickoff station leaves a void at such station until the dogs can advance the midtable billet to its final position at the pickoff station.

The present invention is designed to overcome the abovenoted limitations that are attendant upon the construction and operation of conventional automatic charge tables, and toward this end, it contemplates the provision of a novel apparatus by means of which a charge table may be loaded with billets with full assurance that at all times a billet will be present at the pickoff station providing, of course, that the loading rate does not fall below the consumption rate over a period of time sufficient to cause depletion of the number of billets on the charge table.

Briefly, in carrying out the invention, it is contemplated that as each billet is deposited on the charge table at the loading station, such billet will be pushed forwardly to the fullest extent of which it is capable of being pushed. If such a billet is not preceded by another billet, it will be pushed at least partially, or completely, through the pickoff station and into engagement with a limit switch which terminates its forward movement. If such billet is preceded by one or more billets, the consolidated line or series of such billets is pushed for wards, the limit switch terminating its movement as soon as it is engaged by the leading billet in the series. Immediately thereafter, the lone billet, or the leading billet in the series, as the case may be, is pushed rearwards and centered at the pickofi' station where it is available for pickoff purposes as a preliminary to grinding or surfacing. By such an arrangement, if the supply of billets that are fed to the charge table at the loading station is commensurate with the demand for billets at the pickoff station, each billet is individually pushed forwardly directly from the loading station to the pickoff station. If the supply of billets that are fed to the table at the loading station exceeds the demand for billets at the pickoff station, the billets will accumulate at the pickoff or front end of the table, the series of billets building up progressively in a rearward direction commencing at the pickoff station. This passing of billets past the pickoff station and then returning them to such station is referred to herein as a resetting" operation, and by means of such an operation, each cycle of operation of the apparatus by means of which the reset is attained will terminate with a billet in position at the pickoff station and in position for withdrawal or pickoff on demand. Additionally, by thus resetting an individual billet or an accumulated series of billets at the pickoff station, no consideration need by given to uniformity of billet width, height, or size, a narrow leading billet automatically adjusting itself to the reset operation as well as a wide billet.

The provision of a charge table apparatus such as has been briefly outlined above, and possessing the stated advantages, constitutes the principal object of the present invention.

Other objects and advantages of the invention will readily suggest themselves as the following description ensures.

The invention consists in the several novel features which are hereinafter described and are more particularly defined by the claims at the conclusion hereof.

In the accompanying three sheets of drawings forming a part of this specification, one operative embodiment of the invention is disclosed by way of illustration rather than by way oflimitation.

In these drawings:

FIG. 1 is a diagrammatic view, largely schematic in its representation, showing a charge table equipped with the automatic loading apparatus of the present invention and disclosing interrelated electric and hydraulic circuitry which is capable of actuating the apparatus;

FIG. 2 is a fragmentary view similar to FIG. 1 but entirely schematic in its representation, showing the relative positions of the electrical and hydraulic components before billet-loading operations are commenced;

FIG. 3 is a fragmentary view similar to FIG. 2 but showing the positions of the electrical and hydraulic components when an initial billet is received at the loading station of the charge table;

FIG. 4 is a fragmentary view similar to FIG. 1 but showing the initial billet advanced to the pickoff station with the reset means energized and about to commence its operation;

FIG. 5 is a fragmentary view similar to FIG. 2 but showing the completion of the reset operation;

FIG. 6 is a fragmentary view similar to FIG. 4 but showing a two-billet series advanced to the pickoff station of the charge table with the reset means energized and about to commence its operation;

FIG. 7 is a fragmentary view similar to FIG. 6 but showing the two-billet series in its reset position; and

FIG. 8 is a fragmentary view similar to FIGS. 2 to 7, inclusive, but showing a six-billet series immediately after the reset operation has been completed.

Referring now to the drawings in detail and in particular to FIG. 1, a horizontally elongated table is designated in its entirety by the reference numeral 10 and is adapted to receive successive billets thereon at a loading station LS which is adjacent to the rear end of the table. The table is subject to withdrawal of billets by a pickoff operation at an unloading or pickoff station PS which is located adjacent to the front end of the table. It is to be understood that the charge table and all of the associated mechanism which subsequently will be described in detail, may constitute a subassembly or component of a larger billet handling and conveying system wherein billets from a prior operation are conducted on an infeed conveyor (not shown) which conducts the billets endwise and perpendicular to the axis of the table 10 and deposits them transversely of the table at the extreme rear end of the latter, i.e., at the loading station LS. The thus deposited billets are conducted along the table to the pickoff station PS in a novel manner that will be described presently, and they are withdrawn from the pickoff station, one at a time, as the demand for them arises. The billet withdrawing or pickoff mechanism constitutes no part of the present invention and it has not been disclosed herein, it being deemed sufficient to state that such mechanism includes suitable pickoff arms which successively remove the billets endwise and transverse ly from the table and deposit them on a discharge conveyor (not shown) by means of which they are conducted to a grinding or other operation remote from the table 10.

ln order to conduct the billets which are loaded upon the table 10 at the loading station LS to the pickoff station PS, several means of billet locomotion are contemplated, among these being the use of conveyor attached dogs which may be associated with an intermittently operable conveyor. However, for exemplary purposes a pusher cylinder PC having an extensible billet-engaging plunger 12 associated therewith is disclosed herein, the plunger carrying at one end thereof a fixed piston 14 which is reciprocable in the casing 16 of the cylinder PC. The cylinder PC is actuated under the control of a solenoid-actuated valve SVl, the latter becoming effective each time a billet is deposited on the table at the loading station LS to cause the plunger 12 to push the billet forwardly on the table towards the pickoff station PS. The extent to which a given billet may be pushed forwardly on the table 10 is deter mined by a limit switch LSW having a trip finger 20 which is positioned in the path of movement of the billets adjacent to the front end of the table.

The general arrangement of the charge table and its associated billet-advancing mechanism briefly described above is conventional, the novelty of the present invention residing in the provision of certain billet resetting mechanism at the front end of the table and in the vicinity of the pickoff station PS whereby each actuation of the pusher cylinder PC is accompanied by a resetting operation which results in the shifting of a billet into a proper pickoff position at the pickoff sta tion PS. Such billet resetting mechanism embodies a resetting station RS which is established by a billet support 22. The latter may be considered as being a front extension of the table 10. The billet-resetting mechanism also embodies a reset cylinder RC having a plunger 24 with a fixed piston 26 at one end thereof, said piston being reciprocable in the casing 28 of the reset cylinder RC. The function of the reset cylinder RC is to push a billet which has been moved into the resetting station RS and actuated the finger 20 of the limit switch LSW rearwardly to return the billet to the pickoff station PS through which it previously had passed under the influence of the pusher cylinder PC. The reset cylinder RC is operative under the control of a solenoid-actuated valve SV2 which becomes effective each time the trip finger 20 is moved or actuated by contact with a billet.

The two solenoid-actuated valves SV] and SV2 are substantially identical, the valves being conventional spring-loaded directional valves, each having a spool-type valve element 30 which reciprocates under the control of the solenoid winding W1 in the case of the valve SVl, and a solenoid winding W2 in the case of the solenoid-actuated valve SV2. In the energized condition of the solenoid winding, the valve element 30 directs fluid under pressure from a valve intake port 32 through various internal valve passages to a discharge port 34. In the deenergized condition of the solenoid winding, the valve element 30 directs fluid from the port 32 to a second discharge port 36. In the case of the valve SVl, the port 34 is connected through a conduit 38 with the rear end of the cylinder casing 16 while the port 36 is connected through a conduit 41) with the front end of the cylinder casing. in the case of the valve SV2 similar conduits 42 and 44 connect the ports 34 and 36 with the rear and front ends of the casing 28 of the reset cylinder RC.

Considering now the operation of the pusher cylinder PC and the reset cylinder RC during normal billet-transferring and storing operations, and in associated relation to certain electrical circuitry by means of which the cylinders PC and RC are actuated under the control of billet-loading operations at the rear end of the table and billet pickoff operations at the front end of the table, after closure of the master switch MS of H6. 1, when an initial billet such as the billet B1 as shown in FIG. 3 is deposited on the table 10 at the loading station LS (see FIG. 1), depression of a vertically slidable plunger 50 serves to close the 01 and 02 contacts ofa relay magnet RM]. This closure of contacts takes place prior to energization of the relay magnet RMl, but as soon as the 01 contacts become closed, the magnet becomes energized and locked in its energized condition due to the establishment of a circuit which extends from one side Ll of a power source S, through leads 11, 13, 15, normally closed 01 contacts of the limit switch LSW, leads 17, 19, relay magnet RMll, lead 21, 01 contacts of the magnet RM] (now closed), and lead 23 to the other side L2 of the power source S, With the magnet RMl thus locked in its energized condition and the 02 contacts closed, the solenoidactuated valve SV1 becomes energized through a circuit which extends from the line L1, through leads 11, 13, 15, 01 contacts of the switch LSW, leads 17, 25, 02 contacts of the magnet RM] (now closed), lead 27, solenoid winding W1 of the valve SVl, and lead 29, back to the line L2.

Energization of the solenoid winding W1 of valve SVll shifts the valve element 30 of said valve to a position wherein fluid under pressure is admitted through the conduit 38 to the rear end of the casing 16 of the valve SV1 to move the plunger 12 forwardly and push the adjacent billet forwardly on the table 10 to the position in which it is shown in FIG. 4, wherein the trip finger 20 is engaged by the billet and bears against a limit stop 52, thus terminating further forward movement of the billet and leaving the billet on the support 22 of the reset station RS.

Displacement of the trip finger 20 by the billet B1 serves to open the 01 contacts of the limit switch LSW and to close the 02 contacts of said switch. Opening of these 001 contacts serves to deenergize the previously described circuit through the relay magnet RM1, thus deenergizing this magnet and opening the 01 and 02 contacts thereof. Opening of the 02 contacts of the relay magnet RM1 deenergizes the previously described circuit through the solenoid winding W1 of the valve SV1, thereby reversing the valve and allowing fluid under pressure to flow through the latter to the front end of the cylinder 16 so as to retract the plunger 12 and return the same to the loading station LS preparatory to reception of a second billet at the latter station.

Meanwhile, during return of the plunger 12, closure of the 02 contacts of the limit switch LSW will have energized the magnet RM2 by establishing a circuit from the line L1, through leads 11, 13, 15, 31, 02 contacts of the limit switch LSW (now closed), lead 35, relay magnet RM2, lead 37, normally closed contacts C3, and leads 39, 41 back to the line L2. Such energization of the relay magnet RM2 will cause closure of the 01 and 02 contacts thereof. The 02 contacts are locking contacts and closure thereof will lock the magnet RM2 in its energized condition through a locking circuit extending from the line L1, through leads 11, 13,43, 02 contacts of the magnet RM2 (now closed), lead 35, relay magnet RM2, lead 37, normally closed contacts C3, and leads 39, 41, back to the line L2. Closure of the 01 contacts of the relay magnet RM2 serves to energize the winding W2 of the valve SV2 through a circuit extending from the line L1, through leads 11, 47, 01 contacts of the relay magnet RM2, lead 49, solenoid winding W2, leads 51, 41, back to the line L2.

Such energization of the solenoid winding W2 causes the valve element 30 of the solenoid-actuated valve SV2 to shift to a position wherein fluid under pressure is admitted through the conduit 42 to the rear of the casing 28 of the reset cylinder RC, thus shifting the piston 24 forwardly and pushing the billet Bl rearwardly with respect to the table 10 from the reset station RS to the pickoff station PS where it remains available for pickoff purposes on demand from the grinding station.

As soon as the plunger 24 of the reset cylinder RS reaches its fully extended position, a trip finger 54 which is carried by the piston of such reset cylinder serves to open the contacts C3, thus deenergizin'g the previously mentioned circuit through the relay magnet RM2 whereupon the 01 and 02 contacts thereof become open. Opening of the 02 contacts of said relay magnet RM2 serves to deenergize the previously described circuit through the solenoid winding W2 of the solenoid-actuated valve SV2 and thus restore the valve element 30 thereof to a position where fluid under pressure is conducted to the front end of the casing 28 of the reset cylinder RC so as to retract the plunger 24.

With the plungers of the two valves SVl and SV2 both restored to their normal retracted positions, the billet B1 is left in position at the pickoff station PS for cooperation with the pickoff mechanism by means of which it is transferred to the grinding operation while the loading mechanism awaits delivery of a second billet to the loading station LS. In order to prevent interference between the movements of the plunger 12 of the pusher cylinder PC and the plunger 24 of the reset cylinder RC, the relay magnet RM2 preferably, but not necessarily, is a delayed action magnet in that it is slow to energize and quick to deenergize. Thus, since this magnet remains deenergized for a short period of time after the 02 contacts of the limit switch LSW become closed, the plunger 12 is given time to move rearwardly before the plunger 24 moves to its advanced position, However, if the relay magnet RM2 is not a delayed action magnet, no question of inoperativeness arises since the plunger 24 will operate to assist the plunger 12 in its rearward movement.

The above-described operation of the charge table loading mechanism is repetitive when the rate of billet pickoff at the station PS is equal to the rate of billet delivery at the loading station LS, the reset station RS being thus cleared each time a billet is removed therefrom for subsequent travel of the next succeeding billet along the table directly into the reset station. Such one-billet travel along the table, unimpeded by the presence of other billets, is schematically shown in FIGS. 2 to 5, inclusive, only the valve-energizing and magnet tripping or unlocking contacts being shown in the interests of simplifica tion.

In FIG. 3, the weight of the initial billet B1 forces the plunger 50 downwards against the 02 contacts of the relay magnet RMl, these latter contacts serving to energize the solenoid winding W1 of the valve SVl. Thus, in this view, fluid under pressure is about to be applied to the pusher cylinder PC preparatory to pushing the billet B1 forwardly along the table 10 as indicated by the arrow.

in FIG. 4, the plunger 12 of the pusher cylinder PC is shown in dotted lines as pushing the billet B1 forwardly along the table 12. It is to be noted at this point that although the billet B1 has moved away from the loading station LS, the 02 contacts of the relay magnet RMl remain closed as shown in their dotted line position due to the locking action of the 01 contacts of this magnet. Otherwise, in the absence of the locking contacts, the solenoid winding W1 of the valve SVl would become deenergized before the plunger 12 could complete its forward strokev In FIG. 4, the plunger 12 is shown in full lines as having been moved to its fully advanced position so as to hold the billet B1 against the trip finger of the limit switch LSW. As shown in full lines, the 01 contacts of the limit switch LSW have been opened so as to deenergize the relay magnet RMl and open the 02 contacts thereof, thus deenergizing the solenoid winding W1 of the valve SV1 so that the plunger 12 will be returned to its retracted position as indicated by the full line arrow.

In FIG. 5, the plunger 24 of the reset cylinder RC has returned the billet B1 to the pickoff station PS from the reset station RS and, in so doing, the trip finger 54 has tripped the magnet'holding contacts C3 and thus opened the circuit for the relay magnet RM2. Thus, the 01 contacts of this latter magnet are shown as being open so that the solenoid winding W2 of the valve SV2 is deenergized and the plunger 24 of the valve SV2 is in the course of returning to its retracted position. By the same token, the trip finger 20 of the limit switch LSW has released the 02 contacts of the limit switch LSW, thus allowing the 02 contacts of said limit switch to open and deenergize the solenoid winding W1 of the valve SVl for return of the pusher plunger as described in connection with the disclosure of FIG. 4.

FIG. 6 is illustrative of a condition where a second billet B2 is fed to the loading station LS before the first billet Bl has been withdrawn from the pickoff station PS. In such an instance, depression of the plunger 50 will initiate a full cycle of operation, the cycle proceeding as previously described to push the second billet B2 forwardly on the table 10 and into contact with the billet B1 which has previously been reset by the reset cylinder RC and rests or remains in the position shown in FIG. 5. This second billet B2 then picks up the reset first billet B1 and forces it for the second time against the trip finger 20 of the limit switch LSW, thus setting the limit switch, the relay magnet RM2, and the reset cylinder RC into operation as previously described. This time, however, the reset cylinder RC, instead of resetting a single billet, will reset both billets B1 and B2 to the position wherein they are shown in full lines in FIG. 7, the relay circuitry functioning throughout the cycle in the same manner as the functioning thereof in the case of the resetting ofa single billet.

In FIG. 8 a condition is shown wherein the billets B1 and B2 have both been withdrawn from the pickoff station PS during two previous cycles of operation, billets B3, B4, B5, B6, B7 and B8 have been successively loaded onto the table 10 at the loading station LS and, during consolidation of these six billets, the leading billet B3 has actuated the limit switch LSW six times, resulting in six successive reset operations, each involving an additional billet in the series and with a final resetting of the six-billet series, each cycle of operation involving electrical and hydraulic functions substantially identical to those described in connection with the passage of the initial billet B1 to and from the table 10.

if, for any reason, withdrawal of a billetfrom the pickoff station PS is not immediately followed by replacement thereof with another succeeding billet, manual or automatic switch means is provided whereby the relay magnet RMl may be energized even though no billet may be present at the loading station LS. This means is in the form ofa pushbutton PB (see FIG. 1) which is preferably located in the vicinity of the pickoff station and serves when depressed to establish a circuit extending from the line Ll, through leads 11, 13, 15, 53, pushbutton PB, lead 55, leads 17, 19, magnet RMl, line 21, 01 contacts of the relay magnet RMl, lead 23 back to the line 12. Such energization of the relay magnet RMl has the same effect as that established when the magnet is energized under the control of a billet which rests on the plunger 50 at the loading zone and, consequently, depression of the pushbutton switch PB initiates a complete cycle of operation involving the actuation of the plunger 12 to push whatever billet or billets may be present on the table 10 into the reset station RS for subsequent return to the pickoff station PS.

The invention is not to be limited to the exact arrangement of schematic circuitry, either electrical or hydraulic, disclosed herein, nor is it to be limited to the mechanical components schematically illustrated and described. For example, various means for impelling the billets on the table 10 other than the disclosed cylinder and plunger-type pusher and reset mechanisms are contemplated. If cylinder and plunger mechanisms are employed for billet-impelling purposes, such mechanisms need not be double-acting since spring return pistons involving simplified control valves therefor may be devised within the scope of the present invention. Therefore, only insofar as the invention is particularly pointed out in the accompanying claims is the same to be limited.

Having thus described the invention what I claim as new and desire to secure by letters patent is:

1. In an apparatus for moving billets from a first location to a second location, in combination, a horizontally elongated charge table establishing a loading station adjacent to its rear end and to which billets are successively delivered from said first location, a piekoff station adjacent to its front end from which billets are successively withdrawn for delivery to the second location, and a reset station immediately forwardly of the pickoff station, first energizeable means effective upon energization thereof to impel a billet delivered to the loading station forwardly along the table, through the pickoff station and into the reset station, second energizeable means effective upon energization thereof to impel a billet received at the reset station rearwardly into the pickoff station, means adjacent to the loading station and automatically operable upon reception of a billet at the loading station for energizing said first energizeable means, and means engageable with a billet at the reset station for deenergizing said first energizeable means and for energizing said second energizeable means when a billet arrives at said reset station.

2. In an apparatus for moving billets, the combination set forth in claim 1 and wherein said second energizeable means comprises a fluid cylinder having a billet'engaging plunger, and a solenoid-actuated valve for supplying fluid to said cylinder.

3. In an apparatus for moving billets, the combination set forth in claim 1 and wherein each of said energizeable means comprises a fluid cylinder having a billet-engaging plunger, and a solenoid-actuated valve for supplying fluid to said cylinder. 7

4, In an apparatus for moving billets, the combination set forth in claim 1 and wherein the effective length of said charge table is such that contiguous billet accumulation by longitu dinal stacking of billets under the influence of said first energizeable means may take place on the table between said loading and pickoff stations.

5. In an apparatus for moving billets, the combination set forth in claim 3 and wherein each of said solenoid valves is effective, upon energization thereof, to project the plunger of its associated fluid cylinder into pushing engagement with the billet, and is effective upon deenergization thereof to retract the plunger.

6. In an apparatus for moving billets, the combination set forth in claim 5 and including, additionally, relay means automatically effective upon reception of a billet at the loading station to maintain said first energizeable means energized until the billet has been impelled to the reset station, said limit switch means serving to disable said relay means when the billet arrives at said reset station.

7. In an apparatus for moving billets, the combination set forth in claim 6 and including, additionally, means independent of the reception of a billet at said loading zone for energizing said first energizeable means.

8. In an apparatus for moving billets from a first location to a second location, in combination, a horizontally elongated,

charge table establishing a loading station adjacent to its rear end and to which billets are successively delivered from said first location, a pickoff station adjacent to its front end from which billets are successively withdrawn for delivery to the second location, and a reset station immediately forwardly of the pickoff station, a pusher cylinder adjacent to said loading station and having a piston reciprocable therein and a billetengaging plunger movable with the piston, a first solenoid-aetuated valve effective in a first position to supply fluid under pressure to the cylinder to project said plunger and push a bil' let forwardly on the table and in a second position to supply fluid under pressure to the cylinder to retract the plunger from the thus pushed billet, a reset cylinder adjacent to said reset station and having a piston reciprocable therein and a billetengaging plunger movable with the piston, a second solenoidactuated valve effective in a first position to supply fluid under pressure to the reset cylinder to project the plunger thereof and push a billet rearwardly from the reset station to the pickoff station and in another position to supply fluid under pressure to the reset cylinder to retract such plunger from the rearwardly pushed billet, first relay means automatically effective upon reception of a billet at the loading station for causing said first valve to assume its first position, and second relay means automatically effective upon reception ofa billet at the reset station for causing the second valve to assume its first position and disabling said first relay means.

9. In an apparatus for moving billets, the combination set forth in claim 8 and wherein said second relay means is of the delayed action type.

10. In an apparatus for moving billets, the combination set forth in claim 8 and including additionally means effective when a billet has been pushed rearwardly by the plunger of the reset cylinder and into the pickoff station for disabling the second relay means.

ll. The method of accumulating billets on a charge table between a first billet-receiving,location where the billets are deposited successively on the table and a second billet- 'discharging location where the billets are successively removed from the table, said method comprising impelling each deposited billet forwardly along the table from the first location toward the second location whereby successively deposited billets are caused to form a stack on the table so that each last-deposited billet during forward movement thereof impels the entire series forwardly, said impelling operation causing the leading billet in the series to pass completely through the second location to a reset station immediately forwardly thereof, and thereafter, upon arrival of each leading billet in the series at the reset station, impelling the leading billet, and consequently, the entire series, rearwardly to position such leading billet at the second location for removal therefrom. 

1. In an apparatus for moving billets from a first location to a second location, in combination, a horizontally elongated charge table establishing a loading station adjacent to its rear end and to which billets are successively delivered from said first location, a pickoff station adjacent to its front end from which billets are successively withdrawn for delivery to the second location, and a reset station immediately forwardly of the pickoff station, first energizeable means effective upon energization thereof to impel a billet delivered to the loading station forwardly along the table, through the pickoff station and into the reset station, second energizeable means effective upon energization thereof to impel a billet received at the reset station rearwardly into the pickoff station, means adjacent to the loading station and automatically operable upon reception of a billet at the loading station for energizing said first energizeable means, and means engageable with a billet at the reset station for deenergizing said first energizeable means and for energizing said second energizeable means when a billet arrives at said reset station.
 2. In an apparatus for moving billets, the combination set forth in claim 1 and wherein said second energizeable means comprises a fluid cylinder having a billet-engaging plunger, and a solenoid-actuated valve for supplying fluid to said cylinder.
 3. In an apparatus for moving billets, the combination set forth in claim 1 and wherein each of said energizeable means comprises a fluid cylinder having a billet-engaging plunger, and a solenoid-actuated valve for supplying fluid to said cylinder.
 4. In an apparatus for moving billets, the combination set forth in claim 1 and wherein the effective length of said charge table is such that contiguous billet accumulation by longitudinal stacking of billets under the influence of said first energizeable means may take place on the table between said loading and pickoff stations.
 5. In an apparatus for moving billets, the combination set forth in claim 3 and wherein each of said solenoid valves is effective, upon energization thereof, to project the plunger of its associated fluid cylinder into pushing engagement with the billet, and is effective upon deenergization thereof to retract the plunger.
 6. In an apparatus for moving billets, the combination set forth in claim 5 and including, additionally, relay means automatically effective upon reception of a billet at the loading station to maintain said first energizeable means energized until the billet has been impelled to the reset station, said limit switch means serving to disable said relay means when the billet arrives at said reset station.
 7. In an apparatus for moving billets, the combination set forth in claim 6 and including, additionally, means independent of the reception of a billet at said loading zone for energizing said first energizeable means.
 8. In an apparatus for moving billets from a first location to a second location, in combination, a horizontally elongated charge table establishing a loading station adjacent to its rear end and to which billets are successively delivered from said first location, a pickoff station adjacent to its front end from which billets are successively withdrawn for delivery to the second location, and a reset station immediately forwardly of the pickoff station, a pusher cylinder adjacent to said loading station and having a piston reciprocable therein and a billet-engaging plunger movable with the piston, a first solenoid-actuated valve effective in a first position to supply fluid under pressure to the cylinder to project said plunger and push a billet forwardly on the table and in a second position to supply fluid under pressure to the cylinder to retract the plunger from the thus pushed billet, a reset cylinder adjacent to said reset station and having a piston reciprocable therein and a billet-engaging plunger movable with the piston, a second solenoid-actuated valve effective in a first position to supply fluid under pressure to the reset cylinder to project the plunger thereof and push a billet rearwardly from the reset station to the pickoff station and in another position to supply fluid under pressure to the reset cylinder to retract such plunger from the rearwardly pushed billet, first relay means automatically effective upon reception of a billet at the loading station for causing said first valve to assume its first position, and second relay means automatically effective upon reception of a billet at the reset station for causing the second valve to assume its first position and disabling said first relay means.
 9. In an apparatus for moving billets, the combination set forth in claim 8 and wherein said second relay means is of the delayed action type.
 10. In an apparatus for moving billets, the combination set forth in claim 8 and including additionally means effective when a billet has been pushed rearwardly by the plunger of the reset cylinder and into the pickoff station for disabling the second relay means.
 11. The method of accumulating billets on a charge table between a first billet-receiving location where the billets are deposited successively on the table and a second billet-discharging location where the billets are successiveLy removed from the table, said method comprising impelling each deposited billet forwardly along the table from the first location toward the second location whereby successively deposited billets are caused to form a stack on the table so that each last-deposited billet during forward movement thereof impels the entire series forwardly, said impelling operation causing the leading billet in the series to pass completely through the second location to a reset station immediately forwardly thereof, and thereafter, upon arrival of each leading billet in the series at the reset station, impelling the leading billet, and consequently, the entire series, rearwardly to position such leading billet at the second location for removal therefrom. 